AN EFFICIENT method for the synthesis of new 1,2,3-triazol-4-yl-1,3,4-oxadiazol-2-amines (4a-c) from phenyliso-thiocyanate and 1,2,3-triazolyl-4-hydrazides (3a-c) through cyclo-desulfurization in the presence of sodium acetate is reported. Also, cyclization of 3a-c with concentrated H2SO4 afforded the corresponding triazol-4-ylthiadiazoles )6a-c(. The new products were screened for their antimicrobial activities, and compounds; 4a-c showed excellent antimicrobial activities compared with the reference drugs. Also, the minimum inhibitory concentration (MIC) against the tested organisms was determined in which, compounds 2c and 4a showed the lowest MIC.